Improvement in countersink



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Letters Pat'e'nt No. 92,261, dated July -6, 1869.v

:mauves/:ENT 1N CQNTE'RSINK The Schedule referred to in these Letters Patent and making part of the nml. u

To all whom 'it may concern.-

Beit known that LTR. P. BUTTLEs, ot'Mansiield, in the connty of Tioga, and State of Pennsylvania, have invented certain new and useful Improvements in a Boring-Tool and Counter-sink Combined; and I do hereby declare Vthat the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making part of this speci` cation, and to the letters of reference marked theregu Like letters indicate like parts, wherever they occur.

To enable others skilled in the art to construct and use my invention, I will proceed to describe it.

My invention relates to countersinks; and consists in constructing them fin a novel mannerso that a tool may be adjustedv to them, by means of a spring and catch, or so that they may be adjusted on the to'ol, the object being in both instances to .allow the tool to enter the wood to any. desired distance, whenl the couutersink will operate on the outerend of the hole.

In the drawings- Figure 1 is a perspective view of my conntersink, with tool adj usted to it; l

Figure 2 is a perspective view of my countersink, adjusted on the tool and Figure 3 is a view of Ia tool, with holes in its Shanks.

The'object of my invention is to provide a countersink that may be connected lwith a tool, so as to per-` mitthe latter to penetrate-the wood to any desired distance, and then countersinkv the upper end of the bore, and that may be used either with or without a Just below the head F, on the side of the stem of the conntersink, I attach, by means of a screw,fa, or

,other convenient device, a sp1-ing, B, long enough to extend to the hole c and to its lobse'end,`immediately over the hole c, 1 attacha pin, b, so as readily to` enter the hole c, asv shown'in fig. 1.

The shank Aof the' tool C, I provide with a series of lholes, e, as shown in Iig. 3, so that when this shank is inserted. in the chamber of the stern ofthe countersink it may be adjustcd-andfastened at any desired point, by means of the-piu l), attached to the spring B, as shown in fig. 1.

The countersink, instead of being made, as-sbown in tig. 1, so that the tool may be adjusted in it, I also make as shown in g. 2, so that it may be adjusted o`n the tooll To accomplish this, I chamber the -stem of the counter-sink through and through, and provide'it vwith set-screws, al, for adjusting it'on `a tool. f

This is' done by passing the tool through it and then fastening it at any desired point.

The tool may have a shank, as shown in lie. 2, so

that it :nay be attached to a chambered countersink,

as shown in iig. 1, orhave a conntersiuk attached to it, as shown in fig. 2. y

It is obvious that a countersink might be construct ed on the end of the bit-stock, and then on the side ofthe bitstock be attached a sprng,'with a pin to pass through au opening, andQenter any one cfa sexies of holes in the shank ot the tool, and in this manner, that the countersink be adjusted so as to limit the penetration of the tool.

By the nse'of a tool constructed in this way, the countersink can ,be readily adjusted, so that ,by a single operation of the tool, holes suitable for screws of any particular length may be bored and couutersunk, ready for the insertion of the screw.

ltzmay be used with a bitstock, or have a handle attached to if, and may be attached for 'service to many different kinds oi' tools, such fas screw-drivers, gimlets,.1imlncrs, bits, small angers, drills, and similar tools.

I am aware 4that countersinks have been made with a single cutting lip, and arranged to be attached 1 to a bit or-borng-tool; but such devices haverfailed to operate satisfactorily, for the reasons:

First, that a singleilip is apt to eat in, especially if the wood be cross-grained, `or the hole be boredat an angle, both, of which often occur, and in which eases the holes for the head of the screw will be'left jagged and irregular, or thewood be split out on one side; and j Second; because as these instruments have been made, itis impossibleor difficult to so attach them to the. bit asto make the cutting-lip stand always at 'the .Same or desired angle.

By means of my burr-cutter and tubular stem these diiculties are entirely obviated, and avery perfect tool furnished.

A Having thus described myA invention,

NVhat I claim, is-

A countersink, -having a tubular stem, A, with the burr E formed on its lower end, and arranged to be n'sed in connection with a bit or boring-tool, substan-- tially as desciibed.

. R. P.`BUTTLES.

Witnesses: l

F. W. CLARK, A. J. WEBSTER. 

